Fully Integrated DTL
Original Publication Date: 1986-Oct-01
Included in the Prior Art Database: 2005-Mar-09
This article describes the improvement in circuit density accomplished by the utilization of P-type Schottky barrier diodes (SBDs) as input diodes as well as pull-up "resistors" in diode-transistor logic (DTL) circuits. SBDs on N-type silicon have been widely used in bipolar circuit designs. SBDs on P-type silicon have not been extensively explored even though they exhibit similar electrical characteristics when proper metallurgies are utilized. The improvement in circuit densities is accomplished because: Œ All components of the circuit are integrated over the same Nburied region Œ The circuit has no reach-through contacts; Œ Base contacts are not necessary; Œ No isolation is needed for the N+ buried layer. The figure illustrates a proposed circuit with all devices integrated into one base diffusion.